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2016
Dias, F. S., D. L. Miller, T. A. Marques, J. Marcelino, M. C. Caldeira, J. Orestes Cerdeira, and M. N. Bugalho. "Conservation zones promote oak regeneration and shrub diversity in certified Mediterranean oak woodlands." Biological Conservation. 195 (2016): 226-234. Abstract
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Barbosa, A. R. J. a, A. A. S. a Lopes, S. I. H. a Sequeira, J. P. a Oliveira, A. b Davarpanah, F. b Mohseni, V. S. b Amaral, and R. C. C. a Monteiro. "Effect of processing conditions on the properties of recycled cathode ray tube glass foams." Journal of Porous Materials. 23 (2016): 1663-1669. AbstractWebsite

Cathode ray tube glass waste was used to produce glass foams by a powder sintering route. The glass waste powder was mixed with small amounts (5 and 8 wt%) of coal fly ash, which acted as foaming agent, and the compacts of the mixed powders were heated at different sintering temperatures in the range 600–800 °C for various dwell times (30–120 min). The effect of the different processing conditions on the microstructural characteristics (porosity, pore size and pore size distribution), mechanical resistance and thermal conductivity of the produced foams was investigated. The volume of pores tended to increase with sintering temperature and time, and glass foams (with a porosity higher than 50 %) were only achieved after sintering at 750 °C. The average pore size increased with sintering temperature and dwell time, and pore growth was particularly accentuated at 800 °C, where coalescence of the pores occurred, with a consequent decrease in compressive strength. Selected combinations of the sintering temperature, dwell time and foaming agent led to glass foams with a satisfactory microstructural homogeneity, which exhibited mechanical strength and thermal conductivity values similar to commercial foams used as thermal insulating materials. © 2016, Springer Science+Business Media New York.

Pieranski, Pawel, Simon Čopar, Maria Helena Godinho, and Mallory Dazza. "Hedgehogs in the dowser state." The European Physical Journal E. 39.12 (2016): 121. Abstract
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c Deuermeier, J.a b, Wardenga Morasch Siol Nandy Calmeiro Martins Klein Fortunato H. F. b J. "Highly conductive grain boundaries in copper oxide thin films." Journal of Applied Physics. 119 (2016). AbstractWebsite

High conductivity in the off-state and low field-effect mobility compared to bulk properties is widely observed in the p-type thin-film transistors of Cu2O, especially when processed at moderate temperature. This work presents results from in situ conductance measurements at thicknesses from sub-nm to around 250 nm with parallel X-ray photoelectron spectroscopy. An enhanced conductivity at low thickness is explained by the occurrence of Cu(II), which is segregated in the grain boundary and locally causes a conductivity similar to CuO, although the surface of the thick film has Cu2O stoichiometry. Since grains grow with an increasing film thickness, the effect of an apparent oxygen excess is most pronounced in vicinity to the substrate interface. Electrical properties of Cu2O grains are at least partially short-circuited by this effect. The study focuses on properties inherent to copper oxide, although interface effects cannot be ruled out. This non-destructive, bottom-up analysis reveals phenomena which are commonly not observable after device fabrication, but clearly dominate electrical properties of polycrystalline thin films. © 2016 Author(s).

Martins, Marta, Pedro V. Baptista, Ana Soraia Mendo, Claudia Correia, Paula Videira, Antonio S. Rodrigues, J. Muthukumaran, Teresa Santos-Silva, Ana Silva, Fatima M. C. Guedes da Silva, Joana Gigante, Antonio Duarte, Malgorzata Gajewska, and Alexandra R. Fernandes. "In vitro and in vivo biological characterization of the anti-proliferative potential of a cyclic trinuclear organotin(IV) complex." Molecular Biosystems. 12 (2016): 1015-1023. Abstract
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do de Cabrita, {Maria Rosário Meireles Ferreira}, {Susana Carla Vieira Lino Medina} Duarte, {Helena Maria Louren{\c c}o} Carvalho, and Virgilio Cruz-Machado. "Integration of Lean, Agile, Resilient and Green Paradigms in a Business Model Perspective: Theoretical Foundations." IFAC-PapersOnLine. 49 (2016): 1306-1311. Abstract

In response to the ongoing multidimensional change occurring in the external environment organizations are beginning to recognize management paradigms as Lean, Agile, Resilient and Green (LARG) as drivers to achieve sustainable competitive advantage. The organizations need to adapt and create new business models. A systematic approach to integrate the LARG principles in a Business Model Canvas (BMC) perspective will be a step in the process of achieving the ideal approach. It will provide a broader perspective to identify critical factors to include in the organization's business model, how and why they are related, and which are the conditions and boundaries of these relationships. Although recognizing some limitations when trying to align LARG principles and the building blocks of BMC, this research aims to contribute to the discussion on creating an ideal type of business models to be integrate the LARG paradigm.

Faliya, K., H. Kliem, C. J. Dias, and Ieee. "Investigations of Space Charge Distributions by Atomic Force Microscope." 2016 Ieee International Conference on Dielectrics (Icd), Vols 1-2 (2016): 219-222. AbstractWebsite
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Leal, A. A., A. Dion{\'ısio, M. A. S. Braga, and O. Mateus. "The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment." International Journal of Conservation Science. 7 (2016): 627-646. AbstractWebsite

This study focuses on the assessment of the degradation processes occurring in three sandstone infills of fossilized Late Jurassic ornithopod tridactyl footprints, found in 2001 in a coastline cliff in Porto das Barcas (Lourinhã, Portugal) and exhibited in a museum display since 2004. These dinosaur footprints present nowadays severe decay phenomena compromising their physical integrity and are leading gradually to their loss of value. The deterioration patterns were recorded, a map of their distribution was prepared and several samples were collected both in the dinosaur footprints and in the coastline cliff. Different analytical procedures were applied such as XRD, FTIR, FESEM and Ion Chromatography. A microclimatic survey was also performed and air temperature and relative humidity was measured during eight months both indoor and also outdoor. The decay patterns observed are a combination intrinsic and extrinsic factors the stone material, namely swelling of clay minerals in the rock matrix (smectite and chlorite-smectite mixed-layer), presence of salts (mainly chlorides), application of past conservation treatments (poly(vinyl) acetate and epoxy resins) and with the museum’s indoor thermohygrometric conditions (mainly non-stable hygrometric conditions). This scientific knowledge is therefore essential to the sustainable preservation of this paleontological heritage.

Leal, A. A., A. Dion\{\'ı\}sio, M. A. S. Braga, and O. Mateus. "The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment." International Journal of Conservation Science. 7 (2016): 627-646. Abstract
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Leal, AS, A. Dionísio, M. A. Sequeira Braga, and O. Mateus. "The long term preservation of late jurassic sandstone dinossaur footprints in a museum environment." International Journal of Conservation Science. 7 (2016): 627-646. Abstract
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Silva, F. G. A., M. F. S. F. de Moura, N. Dourado, J. Xavier, F. A. M. Pereira, J. J. L. Morais, and M. I. R. Dias. "Mixed-mode I+II fracture characterization of human cortical bone using the Single Leg Bending test." Journal of the Mechanical Behavior of Biomedical Materials. 54 (2016): 72-81. AbstractWebsite

Abstract Mixed-mode I+II fracture characterization of human cortical bone was analyzed in this work. A miniaturized version of the Single Leg Bending test (SLB) was used owing to its simplicity. A power law criterion was verified to accurately describe the material fracture envelop under mixed-mode I+II loading. The crack tip opening displacements measured by digital image correlation were used in a direct method to determine the cohesive law mimicking fracture behavior of cortical bone. Cohesive zone modeling was used for the sake of validation. Several fracture quantities were compared with the experimental results and the good agreement observed proves the appropriateness of the proposed procedure for fracture characterization of human bone under mixed-mode I+II loading.

Fortunato, Elvira, Diana Gaspar, Paulo Duarte, Lu{\'ıs Pereira, Hugo Águas, António Vicente, Fernando Dourado, Miguel Gama, and Rodrigo Martins. "Optoelectronic Devices from Bacterial NanoCellulose." Bacterial Nanocellulose: From Biotechnology to Bio-Economy (2016): 179. Abstract
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Silva, Pedro ES, Joao L. Trigueiros, Ana C. Trindade, Ricardo Simoes, Ricardo G. Dias, Maria Helena Godinho, and Fernao Vistulo de Abreu. "Perversions with a twist." Scientific reports. 6 (2016). Abstract
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Čopar, Simon, David Seč, Luis E. Aguirre, Pedro L. Almeida, Mallory Dazza, Miha Ravnik, Maria H. Godinho, Pawel Pieranski, and Slobodan Žumer. "Sensing and tuning microfiber chirality with nematic chirogyral effect." Physical Review E. 93.3 (2016): 032703. Abstract
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Bernardo, G. M. S., F. R. Damásio, T. A. N. Silva, and M. A. R. Loja A study on the structural behaviour of FGM plates static and free vibrations analyses. Vol. 136. Composite Structures, 136., 2016. Abstract
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d Deuermeier, J.a b, Bayer Yanagi Kiazadeh Martins Klein Fortunato T. J. M. b. "Substrate reactivity as the origin of Fermi level pinning at the Cu2O/ALD-Al2O3 interface." Materials Research Express. 3 (2016). AbstractWebsite

The reduction of aCu2O layer on copper by exposure toTMAduring the atomic layer deposition of Al2O3 has recently been reported. (Gharachorlou et al 2015 ACS Appl. Mater. Interfaces 7 16428-16439). The study presented here analyzes a similar process, leading to the reduction of a homogeneous Cu2O thin film, which allows for additional observations. Angle-resolved in situ X-ray photoelectron spectroscopy confirms the localization of metallic copper at the interface. The evaluation of binding energy shifts reveals the formation of aCu2O/Cu Schottky barrier, which gives rise to Fermi level pinning in Cu2O. An initial enhancement of the ALD growth per cycle (GPC) is only observed for bulk Cu2O samples and is thus related to lattice oxygen, originating from regions lying deeper than just the first few layers of the surface. The oxygen out-take from the substrate is limited to the first few cycles, which is found to be due to a saturated copper reduction, rather than the oxygen diffusion barrier of Al2O3. © 2016 IOP Publishing Ltd.

Dardouri, Maïssa, João Paulo Borges, and Amel Dakhlaoui Omrani. "Tailoring the morphology of hydroxyapatite particles using a simple solvothermal route." Ceramics International (2016). Abstract
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Duarte, Rafael, Denis Silva da Silveira, João Araújo, and Fernando Wanderley. "Towards a non-conformity detection method between conceptual and business process models." Tenth {IEEE} International Conference on Research Challenges in Information Science, {RCIS} 2016, Grenoble, France, June 1-3, 2016. 2016. 1-6. Abstract
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Dias, C. J. "Transient heat diffusion in multilayered materials with thermal contact resistance." International Journal of Heat and Mass Transfer. 97 (2016): 1001-1009. AbstractWebsite
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Aroso, Ivo M., João C. Silva, Francisca Mano, Ana S. D. Ferreira, Madalena Dionísio, Isabel Sá-Nogueira, Susana Barreiros, Rui L. Reis, Alexandre Paiva, and Ana Rita C. Duarte. "{Dissolution enhancement of active pharmaceutical ingredients by therapeutic deep eutectic systems}." European Journal of Pharmaceutics and Biopharmaceutics. 98 (2016): 57-66. AbstractWebsite

A therapeutic deep eutectic system (THEDES) is here defined as a deep eutectic solvent (DES) having an active pharmaceutical ingredient (API) as one of the components. In this work, THEDESs are proposed as enhanced transporters and delivery vehicles for bioactive molecules. THEDESs based on choline chloride (ChCl) or menthol conjugated with three different APIs, namely acetylsalicylic acid (AA), benzoic acid (BA) and phenylacetic acid (PA), were synthesized and characterized for thermal behaviour, structural features, dissolution rate and antibacterial activity. Differential scanning calorimetry and polarized optical microscopy showed that ChCl:PA (1:1), ChCl:AA (1:1), menthol:AA (3:1), menthol:BA (3:1), menthol:PA (2:1) and menthol:PA (3:1) were liquid at room temperature. Dissolution studies in PBS led to increased dissolution rates for the APIs when in the form of THEDES, compared to the API alone. The increase in dissolution rate was particularly noticeable for menthol-based THEDES. Antibacterial activity was assessed using both Gram-positive and Gram-negative model organisms. The results show that all the THEDESs retain the antibacterial activity of the API. Overall, our results highlight the great potential of THEDES as dissolution enhancers in the development of novel and more effective drug delivery systems.

Barros, A. A., S. Browne, C. Oliveira, E. Lima, A. R. C. Duarte, K. E. Healy, and R. L. Reis. "{Drug-eluting biodegradable ureteral stent: New approach for urothelial tumors of upper urinary tract cancer}." International Journal of Pharmaceutics. 513 (2016). Abstract

© 2016 Elsevier B.V. Upper urinary tract urothelial carcinoma (UTUC) accounts for 5–10{%} of urothelial carcinomas and is a disease that has not been widely studied as carcinoma of the bladder. To avoid the problems of conventional therapies, such as the need for frequent drug instillation due to poor drug retention, we developed a biodegradable ureteral stent (BUS) impregnated by supercritical fluid CO 2 (scCO 2 ) with the most commonly used anti-cancer drugs, namely paclitaxel, epirubicin, doxorubicin, and gemcitabine. The release kinetics of anti-cancer therapeutics from drug-eluting stents was measured in artificial urine solution (AUS). The in vitro release showed a faster release in the first 72 h for the four anti-cancer drugs, after this time a plateau was achieved and finally the stent degraded after 9 days. Regarding the amount of impregnated drugs by scCO 2 , gemcitabine showed the highest amount of loading (19.57 $μ$g drug /mg polymer: 2{%} loaded), while the lowest amount was obtained for paclitaxel (0.067 $μ$g drug /mg polymer : 0.01{%} loaded). A cancer cell line (T24) was exposed to graded concentrations (0.01–2000 ng/ml) of each drugs for 4 and 72 h to determine the sensitivities of the cells to each drug (IC 50 ). The direct and indirect contact study of the anti-cancer biodegradable ureteral stents with the T24 and HUVEC cell lines confirmed the anti-tumoral effect of the BUS impregnated with the four anti-cancer drugs tested, reducing around 75{%} of the viability of the T24 cell line after 72 h and demonstrating minimal cytotoxic effect on HUVECs.

Antognini, A., K. Schuhmann, F. D. Amaro, P. Amaro, M. Abdou-Ahmed, F. Biraben, T. L. Chen, D. S. Covita, A. J. Dax, M. Diepold, L. M. P. Fernandes, B. Franke, S. Galtier, A. L. Gouvea, J. Götzfried, T. Graf, T. W. Hänsch, M. Hildebrandt, P. Indelicato, L. Julien, K. Kirch, A. Knecht, F. Kottmann, J. J. Krauth, Y. W. Liu, J. Machado, C. M. B. Monteiro, F. Mulhauser, F. Nez, J. P. Santos, J. M. F. dos Santos, C. I. Szabo, D. Taqqu, J. F. C. A. Veloso, A. Voss, B. Weichelt, and R. Pohl. "{Experiments towards resolving the proton charge radius puzzle}." Vol. 113. EPJ Web of Conferences, 2016. 01006. Abstract
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Silva, João C., Alexandre A. Barros, Ivo M. Aroso, Dario Fassini, Tiago H. Silva, Rui L. Reis, and Ana Rita C. Duarte. "{Extraction of Collagen/Gelatin from the Marine Demosponge Chondrosia reniformis (Nardo, 1847) Using Water Acidified with Carbon Dioxide - Process Optimization}." Industrial and Engineering Chemistry Research. 55 (2016): 6922-6930. Abstract

Marine sponges are a rich source of natural bioactive compounds. One of the most abundant valuable products is collagen/gelatin, which presents an interesting alternative source for pharmaceutical and biomedical applications. We have previously proposed an innovative green technology for the extraction of collagen/gelatin from marine sponges based in water acidified with carbon dioxide. In this work, we have optimized the process operating conditions toward high yields and collagen quality as well as to reduce extraction procedure duration and energy consumption. The process extraction efficiency is higher than 50{%}, corresponding to a yield of approximately 10{%} of the sponge dry mass, obtained for mild operating conditions of 10 bar and 3 h. The extracted material was characterized by scanning electron microscopy (SEM), rheology, Fourier transformed infrared spectroscopy (FTIR), circular dichroism (CD), amino acid analysis, and SDS-PAGE. The extracts were found to be composed of highly pure mixtures of co...

Duarte, Ana Rita C., Devid Maniglio, Nuno Sousa, João F. Mano, Rui L. Reis, and Claudio Migliaresi. "{From honeycomb- to microsphere-patterned surfaces of poly(lactic acid) and a starch-poly(lactic acid) blend via the breath figure method.}." Journal of applied biomaterials {&} functional materials. 15 (2016). AbstractWebsite

BACKGROUND This study investigated the preparation of ordered patterned surfaces and/or microspheres from a natural-based polymer, using the breath figure and reverse breath figure methods. METHODS Poly(D,L-lactic acid) and starch poly(lactic acid) solutions were precipitated in different conditions - namely, polymer concentration, vapor atmosphere temperature and substrate - to evaluate the effect of these conditions on the morphology of the precipitates obtained. RESULTS The possibility of fine-tuning the properties of the final patterns simply by changing the vapor atmosphere was also demonstrated here using a range of compositions of the vapor phase. Porous films or discrete particles are formed when the differences in surface tension determine the ability of polymer solution to surround water droplets or methanol to surround polymer droplets, respectively. In vitro cytotoxicity was assessed applying a simple standard protocol to evaluate the possibility to use these materials in biomedical applications. Moreover, fluorescent microscopy images showed a good interaction of cells with the material, which were able to adhere on the patterned surfaces after 24 hours in culture. CONCLUSIONS The development of patterned surfaces using the breath figure method was tested in this work for the preparation of both poly(lactic acid) and a blend containing starch and poly(lactic acid). The potential of these films to be used in the biomedical area was confirmed by a preliminary cytotoxicity test and by morphological observation of cell adhesion.